Saturday, December 19, 2015

Another trove of fossils in Oklahoma

Creationists have to close their eyes very, very tightly and
keep saying “Na na na I can’t hear you” when they encounter evidence, which
surrounds them, of evolution. One of the places of which this is most true is
Oklahoma. Oklahoma has lots of fossils that demonstrate the old age of the
Earth, and is also one of the hotbeds of creationism. Oklahoma creationists
are, therefore, some of the people who are most skillful at selectively
ignoring whatever they do not want to see.

Yesterday I took a hike with Nature Conservancy members at Nickel Preserve, near Tahlequah, Oklahoma. If you do not know about
this wonderful organization, please follow the link provided. We climbed a very
steep slope with loose soil to some limestone bluffs, from which we could look
out over the bottomland flats and the forested hills. I felt like one of my
Cherokee ancestors (Tahlequah has been the capital of the Cherokee Nation of
Oklahoma since 1839) who thought nothing of running up and down hills in search
of game. Near the bluffs, but not elsewhere in the forest, there were lots of
sugar maples, which are abundant in the eastern deciduous forests but in
Oklahoma are mainly found near cliffs.

Certain layers of the limestone had crinoid fossils.
Crinoids are echinoderms (related to starfish) that like inside of limestone
stalks that they create. The stalks look superficially like a stack of coins.

Some of the limestone layers were crammed with the fossils.

But other layers were not. In this photo, you can see that
the crinoid fossils are restricted to one narrow layer.

There were just a few lampshell fossils:

The reason that some layers had lots of fossils and others
did not was probably that the fossiliferous layers are remnants of shallow
water environments, while the other layers are remnants of sediments deposited
farther from shore. Shallow water, permeated by sunlight, often has more and
larger sessile organisms, because there is more food at the base of the food
chain, than in deeper, darker waters. These limestone layers are a record of
changes in sea level over the course of many thousands of years. The reason
that the fossil deposits are almost entirely crinoids in this location, and almost
entirely mollusks in other locations, in Oklahoma, may be due to the advantage
of numbers. Once crinoids are abundant, their massive reproduction keeps
mollusks from literally being able to gain a foothold; and vice versa. This is
one reason why crinoids and nearly every other kind of sessile invertebrate are
rare today in mussel beds.

The point is that these fossils could not possibly represent
the random sloshings of Noachian flood waters. If all of these layers were
deposited during a single Flood of Noah, why do some layers have fossils and
others do not, and why are the fossils not a random selection of animals that
lived on the Earth the day that Noah went into the Ark and closed the door?
Creationists have no explanation whatsoever for why the Flood waters would have
sorted out fossils into an evolutionary order.

A cache is where you hide a lot of things (from French cacher, to hide); a trove is where you
find a lot of things (from French trouver,
to find). The crinoid cliffs northeast of Tahlequah, Oklahoma is definitely
a trove of evidence, one which tells us about the past history of the Earth.

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Honest Ab

Honest Ab is Stan Rice, a botanist who studied a little weed with heart-shaped leaves, Abutilon theophrasti (Ab). He started this blog in 2009, 200 years after the births of Darwin and Honest Abe. Click image for his web page.